HARD CONTROLS ON TOUCH PANEL SURFACE
Original Publication Date: 1988-Aug-31
Included in the Prior Art Database: 2004-Apr-04
Xerox Disclosure Journal
In commercial electrophotographic printing machines, touch screen are presently being introduced as operator interfaces. The touch screen is positioned over a cathode ray tube. The cathode ray tube displays graphic symbols which may be varied in accordance with the selected symbol. The touch screen has a plurality of infrared beams defining a grid. As the operator selects the desired graphic symbol, the beams are broken by the operator's finger. The control system, based upon the signal from the broken beams, actuates the appropriate machine program corresponding to the selected graphic symbol. Recently acoustic touch screens have been developed. An acoustic touch screen has a flat glass with acoustic transducers on its surface. A screen of this type may also be used in conjunction with a cathode ray tube in lieu of an infrared touch screen. Hereinbefore, the touch screen and cathode ray tube were complemented with push buttons for a numerical key pad, starustop print, etc. These push button controls may be eliminated by extending the area of the touch screen beyond the cathode ray tube. This marginal region beyond the cathode ray tube has fixed graphic symbols thereon. Thus, the display now includes a cathode ray tube having variable graphic symbols and region outside the cathode ray tube with fixed graphic symbols. The touch screen extends over both regions. Thus, the region outside the cathode ray tube with the fixed graphic symbols beneath the touch screen replaces the previously used push buttons.